(1) Field of the Invention
This invention relates to lawn mowers. In particular it relates to the generation of electricity for electrically powered hand and rider lawn mowers and for auxiliary electrical hand tools used in connection with yard care.
(2) Description of the Prior Art
Lawn mowers arbitrarily fall into three categories, electrically powered, gasoline powered or manually operated. Electrically powered lawn mowers are usually the least expensive but pose a danger because of the need for a lengthy power cord which may be struck by the blades of the lawn mower. Gasoline powered mowers are apt to be more expensive because they have more component parts and they are more complicated to operate than electrically powered lawn mowers. Gasoline powered mowers may have either a direct drive or an electrical drive. Manual lawn mowers have mechanical linkage to rotate a ferris wheel type of blade array as the lawn mower is pushed along on its wheels.
Bailey, U.S. Pat. No. 2,229,912, in 1941, disclosed an electrical generator powered by a gasoline engine. The generator was used to run a motor which displaced penetrable matter, such as earth. Gooch, in 1950, U.S. Pat. No. 2,523,014, disclosed the use of a gasoline engine or an electrical motor as prime movers to operate a hydraulically driven lawn mower.
Smith, in 1955, U.S. Pat. No. 2,702,448, disclosed a rotary type hand lawn mower in which power for driving the cutter is supplied from a battery mounted on the mower. Aside from the usual advantages of an electrically powered lawn mower, such as low cost and quietness, Smith emphasized the safety feature of eliminating the long power cord. Wilgus, in 1965, U.S. Pat. No. 3,212,244, disclosed a similar rechargeable storage battery to power a hand lawn mower but with the addition of a means to vertically adjust the position of the motor and the blades.
Thorud et al, in 1972, U.S. Pat. No. 3.696,593, introduced a Bendix type electrical starter powered by batteries carried on the handle of the hand lawn mower. He mentions the many difficulties associated with recoil and impulse starters previously in use to start gasoline powered lawn mowers. In 1982, Thomas et al, U.S. Pat. No. 4,333,302, disclosed the use of both an a.c. motor and a d.c. motor mounted side by side on an electrically powered lawn mower. The motors could be used singly or in tandem for added power. The mower operated on a d.c. battery. Gears and clutch arrangements provided for alternative uses of the a.c. and d.c. drive motors. Ando et al, in 1986, U.S. Patent No. 4,618,019, disclosed a motor cycle engine with two dynamos. A socket for taking off the output of the second dynamo is provided on the body of the motor cycle.
Although the prior art has offered means for the elimination of lengthy power cords for electrically powered lawn mowers, none discloses a detachable, independently operated power source which not only serves the needs for lawn mowing but for auxiliary electrical hand tools as well. The present invention meets the needs for grass cutting as well as the operation of weed eating, blowing, hedge trimming, and edging, regardless of the remoteness of the area in the yard being groomed. Also, the apparatus of the present invention constitutes a detachable, self contained generator for emergency uses as power for RV's (recreational vehicles), sawing and drilling operations, lights, pumps and anything electrical. In addition, the apparatus assures operation of the electrically operated lawn mowers and auxiliary electrical hand tools despite local power outages. Also, the 12 volt d.c. current of the apparatus of the present invention is available for recharging batteries of boats and automobiles.
Prior art known to this inventor includes the following U.S. Pat. Nos.:
______________________________________ 2,229,912 1/1941 Baily 2,523,014 9/1950 Gooch 2,702,448 2/1955 Smith 3,212,244 10/1965 Wilgus 3,969,593 10/1972 Thorud et al 4,333,302 1/1982 Thomas et al 4,618,019 10/1986 Ando et al ______________________________________